The two-year-old law allowing undercover surveillance of released sex criminals has helped prevent repeat offenses, Ronit Zar, commander the Prisons Service's Supervision Unit, told the Knesset's Constitution, Law and Justice Committee on Wednesday. Under the 2006 law, before release, each sex offender must undergo an assessment to determine the risk they pose to society. Based on the assessment, a permit for surveillance can be obtained. A variety of methods, including photography and video, are used to monitor the subjects' movement. "If you just visit [a past offender] at home, you cannot truly judge their behavior," Zar said. "We need to learn how they behave outside of their homes, and give them reminders through surveillance." The threat of undercover supervision has led offenders to think twice before they act, Zar told the committee. Conflicting interpretations of the proper way to evaluate and monitor the offenders were voiced at the meeting. Hagit Lernau, deputy chief of the Public Defenders Office, told The Jerusalem Post she believed the Supervision Unit was being used more widely than permitted, and that the evaluation process needed to be conducted with more "privacy and dignity." Currently, a panel judges the offender's threat to society, she said. Offenders must reveal their most personal moments, thoughts and history. "I think the professional standards need to be changed," Lernau said. "We need to rethink how to perform risk assessments in a way that is more humane." The victims' voices needed to be heard during offender evaluations, to create a more productive and accurate assessment, Ruti Eldar, lawyer for the Noga Center for Victims of Crime, told the Post. "[The evaluation board] needs to hear what happened," she said, adding that she approved of the undercover supervision that had been taking place. "The more surveillance, the better," Eldar said. Committee chairman MK Menahem Ben-Sasson (Kadima) said the government should fully support the undercover supervision. He said electronic techniques would likely be used in the future to better monitor offenders' behavior. "There are currently good explanations that [undercover surveillance] is in full accordance of the law," he said. "But in the future, we may need a better definition." The Law Committee plans to revisit the issue in a few months.